ME1 LE issue: Cannot shoot for a brief time after using a power or melee

I thought it was something I was doing. I'm pretty certain I've had this happen a few times. I'm playing a Sentinel, so no Immunity for me. I'll watch for a pattern if it keeps happening.

Sometimes it happens to me too. I'm using mouse and keyboard on Origin.

I've notice some of this...but it isn't consistent by any stretch.  Lag related?  I've also had dialogue pause briefly mid-sentence, then pick up again by repeating a word and continuing.... All of this and worse on Feros (Reference my other thread).  For the inability to shoot after melee... I was punching the creapers to knock them down so they couldn't spray me with acid.  It was working, but there was frequently a moment where I could not commence shooting them while I had them knocked down.